|Intervales, São Paulo, Brazil
The Buff-bellied Puffbird is distributed in south-east Brazil and adjacent areas of Paraguay and Argentina.
It has often been regarded as a sub-species of White-necked Puffbird N. macrorhynchus, but Rasmussen & Collar seperate the two in HBW, Vol 7, Page 105 and this is becoming generally accepted. See also Kevin Zimmer's proposal here.
It differs most noticeably from White-necked Puffbird in being smaller, having a rufous belly and having grey rather than black patches on the flanks.